Update cloudwatch_log_subscription_filter.html.markdown (#13659)
Update cloudwatch_log_subscription_filter.html.markdown (#13659)

Currently CloudWatch log subscription supports Lambda as a destination. And we can use `aws_cloudwatch_log_subscription_filter` resource for creating subscriptions with Lambda as a destination, but it needs some additional actions. I described them in description, but feel free to improve description if you can say the same better.
This change will help better understand abilities of using this resource.
terraform-providers/terraform-provider-aws,charles-at-geospock/terraform-provider-aws,Ninir/terraform-provider-aws,charles-at-geospock/terraform-provider-aws,Ninir/terraform-provider-aws,kjmkznr/terraform-provider-aws,nbaztec/terraform-provider-aws,terraform-providers/terraform-provider-aws,ClementCunin/terraform-provider-aws,ashinohara/terraform-provider-aws,ashinohara/terraform-provider-aws,Ninir/terraform-provider-aws,terraform-providers/terraform-provider-aws,nbaztec/terraform-provider-aws,charles-at-geospock/terraform-provider-aws,kjmkznr/terraform-provider-aws,kjmkznr/terraform-provider-aws,ClementCunin/terraform-provider-aws,ClementCunin/terraform-provider-aws,Ninir/terraform-provider-aws,ashinohara/terraform-provider-aws,ClementCunin/terraform-provider-aws,charles-at-geospock/terraform-provider-aws,kjmkznr/terraform-provider-aws,ashinohara/terraform-provider-aws,nbaztec/terraform-provider-aws,nbaztec/terraform-provider-aws,terraform-providers/terraform-provider-aws